1. Field of the Invention
This invention relates to a vehicle hitch receiver tube reinforcement ring, to a vehicle hitch including the reinforcement ring, and to a method for making the hitch.
2. Background Art
One type of vehicle hitch for towing trailers or other wheeled vehicles includes a hitch receiver tube that is mounted on the vehicle extending longitudinally and opening in a rearward direction to receive a ball hitch tongue. Such receiver tubes are conventionally made from flat stock that is formed into a square shape and then welded to provide a longitudinal seam that is usually located on a top wall but is essentially unobservable after painting of the receiver tube. To strengthen the construction, a reinforcement ring is conventionally secured around the rear end portion of the receiver tube by welding. For automobile and light truck towing, the receiver tube will normally have a thickness of about one eighth to one fourth of an inch and the reinforcement ring will have a thickness of about one eighth inch. Such reinforcement rings like the receiver tubes are also made from flat stock that is formed into a tube and welded prior to being cut to a length of about one half to one inch. For an example of such receiver tubes and reinforcement rings see U.S. Pat. No. 5,184,840 Edwards.
U.S. Pat. No. 5,620,198 Borchers discloses a trailer hitch receiver which has a reinforced lip which apparently is manufactured by upsetting the receiver tube so as to have an increased thickness at its rear end. The Borchers patent discloses a collar made of plastic, aluminum or stainless steel to provide surface finish protection by preventing the propagation of rust at surface scratching caused by a hitch tongue and ball assembly as it is inserted into the receiver box.
Other prior art patents noted by during an investigation conducted in connection with the present invention include U.S. Pat. No. Des. 409,960 Young; U.S. Pat. No. 1,903,220 Lemert; U.S. Pat. No. 3,352,574 Brian; U.S. Pat. No. 3,679,231 Derr, Jr.; U.S. Pat. No. 3,694,006 Good et al.; U.S. Pat. No. 3,768,837 Reese; U.S. Pat. No. 3,782,761 Cardin, Sr.; U.S. Pat. No. 3,838,872 Fullhart; U.S. Pat. No. 3,911,960 Flimon; U.S. Pat. No. 4,032,170 Wood; U.S. Pat. No. 4,040,641 Riecke; U.S. Pat. No. 4,509,770 Young et al.; U.S. Pat. No. 4,852,902 Young et al.; U.S. Pat. No. 5,148,835 Clark; U.S. Pat. No. 5,203,194 Marquardt; U.S. Pat. No. 5,277,448 Colibert; U.S. Pat. No. 5,695,204 Ford; U.S. Pat. No. 5,897,126 Morris; and U.S. Pat. No. 6,241,271 Belinky as well as United Kingdom patent document 2 257 100 A.
An object of the present invention is to provide an improved reinforcement ring for a vehicle hitch receiver tube.
In carrying out the above object, the vehicle hitch receiver tube reinforcement ring of the invention includes a square stamping having four elongated portions each of which has opposite ends connected to ends of adjacent elongated portions such that the elongated portions cooperate to define a square opening. The elongated portions each have a J-shaped cross section including a front flange and a rear flange. Each front flange has opposite ends connected to ends of adjacent front flanges such that the front flanges can extend around the hitch receiver tube. Each rear flange extends inwardly from the associated front flange toward the center of the square opening with a curved shape having a distal extremity, and each rear flange has opposite ends connected to ends of adjacent rear flanges such that the rear flanges can cover an axial end of the hitch receiver tube with its distal extremity in engagement therewith to provide an uninterrupted contour between the rear flanges and the interior of the hitch receiver tube.
The hitch receiver tube reinforcement ring has the distal extremity of each rear flange constructed to include an engagement portion for axially engaging the axial end of the hitch receiver tube, an inner surface that provides an uninterrupted contour with the interior of the hitch receiver tube, and a chamfer that facilitates insertion of a hitch tongue into the hitch receiver tube.
Another object of the present invention is to provide an improved vehicle hitch.
In carrying out the above object, the vehicle hitch of the invention includes a hitch receiver tube for mounting on a vehicle in a generally longitudinally extending direction. The hitch receiver tube has a square cross section including inner and outer surfaces defining square shapes, and the hitch receiver tube has an axial end that extends between the inner and outer surfaces of the hitch receiver tube and faces rearwardly with respect to the associated vehicle upon mounting thereon. The vehicle hitch also includes a reinforcement ring embodied by a square stamping having four elongated portions each of which has opposite ends connected to ends of adjacent elongated portions such that the elongated portions cooperate to define a square shape. The elongated portions each have a J-shaped cross section including a front flange and a rear flange. Each front flange has opposite ends connected to ends of adjacent front flanges with the front flanges extending around the hitch receiver tube in engagement with its outer surface. Each rear flange extends inwardly from the associated front flange toward the center of the square opening with a curved shape having a distal extremity. Each rear flange has opposite ends connected to ends of adjacent rear flanges with the rear flanges covering the axial end of the hitch receiver tube and with the distal extremity of the rear flange in engagement with the axial end of the hitch receiver tube to provide an uninterrupted contour between the rear flanges and the inner surface of the hitch receiver tube. A weld secures the reinforcement ring to the hitch receiver tube.
The vehicle hitch has the distal extremity of each rear flange of the reinforcement ring constructed to include an engagement portion that engages the axial end of the hitch receiver tube, an inner surface that provides an uninterrupted contour with the inner surface of the hitch receiver tube and a chamfer that facilitates insertion of a hitch tongue into the hitch receiver tube.
The construction of the hitch receiver tube of the hitch has bottom and top walls spaced vertically from each other and a pair of side walls spaced laterally from each other, with each front flange of the reinforcement ring having a front edge, and with a weld that secures the bottom wall of the hitch receiver tube to a front edge of the front flange of an adjacent elongated portion.